Objective: Describe the changes in hearing ability and progression of disease over time in subjects with neurofibromatosis Type 2 enrolled in a multicenter natural history study of vestibular schwannomas in neurofibromatosis Type 2.
Study design: Retrospective clinical study.
Setting: International neurofibromatosis Type 2 tertiary care centers.
Patients: Study participants had a clinical diagnosis of neurofibromatosis Type 2, at least one untreated vestibular schwannoma, and were at least 5 years old. Sixty-three subjects (108 ears) with audiology data at either short-term follow-up (7 mo-2 yr) or long-term follow-up (3-5 yr) after diagnosis were examined in this study.
Main outcome measures: Changes in four-frequency pure-tone average and speech discrimination score before any treatment intervention for both follow-up intervals.
Results: Within 2 years of the diagnosis of neurofibromatosis Type 2, 27% of the ears experienced a significant loss in pure-tone average relative to diagnosis, and 73% of the ears experienced no significant change in hearing.
Conclusion: Newly diagnosed neurofibromatosis Type 2 patients who do not require immediate treatment of both vestibular schwannomas are likely to have stable hearing in the unoperated ear(s) for approximately 1 to 2 years.